I have a 2019 Ram 3500 Longhorn Mega Cab. I was launching my boat this weekend from the shore (no ramp) so I had it in 4 low. When I pulled the trailer out, every caution light came on at once...serv 4x4, ABS, Brake, front collision, check engine, and some others I forgot. The indicator light for 4x4 went out completely, and the truck would not shift out of 4-low. I eventually found a blown fuse -F77 DTCM/TCM/FAD MOD 10 amp. I replaced the fuse and all of the lights went out except for the check engine. The 4x4 indicator light came back on, and I was able to shift back into 2wd and get home. The check engine light stayed on, but otherwise everything was normal. Taking it back to the dealer for the light tomorrow. I mainly wanted to post this because it could keep someone from being stranded or having to call a tow truck, and possibly save them a lot of time checking fuses. Has anyone else had this this happen? Any idea why, or what I can do to keep it from happening again? My rear tires were in the water, but the level was below the center of the axles. The trailer lights were plugged in (I have to keep them plugged in to release the electric brakes when backing) and none of the trailer fuses popped.